Such robotic vacuum cleaner is disclosed in US-A-2002/0174506. This publication describes an autonomous vacuum cleaner comprising technology that can automate routine household tasks eliminating the need for humans to perform these repetitive and time consuming tasks. The vacuum cleaner can autonomously clean a room while the vacuum cleaner is travelling around on the floor of the room. Thereby, the path of the vacuum cleaner can be controlled based on observations of its environment by cameras or other observation means, such as sonar sensors or infrared sensors. Additionally, sensor means are present at one or more sides of the mobile device in order to detect physical contact between the mobile device and stationary objects (obstacles) on the floor of the room. The sensor means generate appropriate control signals for controlling the path of travel of the vacuum cleaner. The vacuum cleaner described in US-A-2002/0174506 consists of two modules, a main module comprising the vacuum fan and a debris collection compartment, and a cleaning head module connected with the main module by a hose, through which hose the debris is transported from the cleaning head module to the main module.
The mobile robotic vacuum cleaner has to find its path of travelling around and between stationary objects in its environment. When the moving vacuum cleaner touches a stationary object, its direction of travelling has to be changed, so that collision with the stationary object is avoided. Therefore, physical contact with such stationary object is detected in order to adapt the direction of movement of the vacuum cleaner, for example in the opposite direction, away from the stationary object.